<template>
    <div>
        <h1>当前求和为：{{he}}</h1>
        <h3>当前求和放大10倍为：{{bigSum}}</h3>
        <h3>我在{{xuexiao}}学习{{xueke}}</h3>
        <select v-model.number="n">
            <option value="1">1</option>
            <option value="2">2</option>
            <option value="3">3</option>
        </select>
        <button @click="increment">+</button>
        <button @click="decrement">-</button>
        <button @click="incrementOdd">当前求和为奇数再加</button>
        <button @click="incrementWait">等一等再加</button>
    </div>
</template>

<script>
    import {mapState, mapGetters} from 'vuex'

    export default {
        name: "Count",
        data() {
            return {
                n: 1
            }
        },
        methods: {
            increment() {
                this.$store.commit('JIA', this.n);
            },
            decrement() {
                this.$store.commit('JIAN', this.n);
            },
            incrementOdd() {
                this.$store.dispatch('addOdd', this.n);
            },
            incrementWait() {
                this.$store.dispatch('addWait', this.n);
            }
        },
        computed: {
            // 靠程序员自己亲自去写计算属性
            /*he() {
                return this.$store.state.sum;
            },
            xuexiao() {
                return this.$store.state.school;
            },
            xueke() {
                return this.$store.state.subject;
            },*/
            // 借助 mapState 生成计算属性，从 state 中读取数据（对象写法）
            ...mapState({he:'sum', xuexiao:'school', xueke:'subject'}),
            /********************************/
            /*bigSum() {
                return this.$store.getters.bigSum;
            }*/
            // 借助 mapGetters 生成计算属性，从 getters 中读取数据（对象写法）
            // ...mapGetters({bigSum:'bigSum'})
            // 借助 mapGetters 生成计算属性，从 getters 中读取数据（数组写法）
            ...mapGetters(['bigSum'])
        },
        mounted() {
            const x = mapState({he:'sum', xuexiao:'school', xueke:'subject'});
            console.log(x);
        }
    }
</script>

<style>
    button {
        margin-left: 5px;
    }
</style>